This invention relates to a machine and method for processing webs in which the web is longitudinally compressed under the influence of driving forces provided by two rotating rolls and retarding forces applied by stationary members.
In some known machines used for corrugating paper, the two rolls are themselves corrugated and the roll corrugations are mated such that the paper, when passed through the nip, becomes corrugated.
Lorenz, U.S. Pat. No. 1,689,037, shows a pair of mated serrated rolls for corrugating paper, followed by a pair of guide bars defining a corrugated channel through which the paper passes on its way to a pair of creping rolls.
In Cannard, U.S. Pat. No. 1,680,203, a web is creped by passing it into the nip between two drive rolls each having disks alternating with spacer elements. The disks of one roll may be offset relative to the other roll. After passing through a relatively long confining passage, the web is engaged by slower rotating rolls which cause the web to crowd together in the long passage to form transverse crepes. The long passage is bounded by two sets of long, thin members, the forward ends of which are tapered and disposed in the spaces between the disks of the drive rolls.
Molla, U.S. Pat. No. 2,814,332, shows a paper-forming machine in which two serrated rolls with toothed lands impress a pattern on the web and a set of fingers interdigitated in the valleys of the lower roll strip the web off the lower roll.